Brake Overhaul - picture heavy

[yorkie_chris]

Nah the reservoir is kinda sealed, but the membrane on top of it allows a change in volume.

so drain the system first, then take brake off to clean, replace brake, refill system, got you

[punyXpress]

What's behind the pistons will flood out, & that in the pipes will trickle out unless you pull the lever.
How do I know?
It's an age thing, so guess which I am.

[yorkie_chris]

No, pump pistons out, will get rid of most of the old fluid, then remove caliper. Catch the old stuff in a tin or with rags or something.

[yorkie_chris]

Originally Posted by punyXpress

What's behind the pistons will flood out, & that in the pipes will trickle out unless you pull the lever.
How do I know?
It's an age thing, so guess which I am.

Indeed that will close transfer port and stop you losing fluid out of the reservoir.

[punyXpress]

If one piston is nearly out & the other hasn't moved, hold the moving one with a narrow G clamp so the other is forced out.

I've done this on several different bikes, good job to do, time comsuming but very rewarding…
tip..
hold one piston down with a clamp, pump the brake, let the other piston come out a bit (halfway), hold it with a clamp, release the other piston from clamp, pump the brakes till the piston comes out… then your other piston will be halfway out and easier to get out…
what I do is clean one by one though….but I take the caliper completely off the bike and use an air compressor to pop the pistons out, clamp x number of pistons down (will depend on bike) and put air in to pop the free one out..clean, replace seals, put back in…
then repeat this for the other pistons
Also by using this method of not allowing the piston to come out completely, you can clean the pistons a bit, using a tooth brush.
this helps to get rid of some of the road muc and release the pistons a bit…
(in case you can't be bothered to go through all the replacing seals, new fluid in, bleeding brakes stuff….)

Originally Posted by yorkie_chris

Indeed that will close transfer port and stop you losing fluid out of the reservoir.

So I was right the first time around?

Aw man my head hurts now.

[Dave20046]

Just to clarify what's the quickest easiest way to efectively clean up the brakes without faffing around draining the system?
Is there one.

[timwilky]

why are people so worried about draining the system. You need to change your fluid every couple of years, it is cheap, what is the problem?.

Brakes are what keep you alive, the fluid is an important part of the brake system, don't compromise. Do the job properly.

Use the on board extraction tool, as the pistons get pumped, a small g clamp to stop them popping until all are pushed out and then remove clamps, remove pistons, give them a polish. remove old seals, clean out the calipers properly, do not score anything, reassemble with a bit of red rubber grease on the new seals.

New fluid, bleed, and enjoy